The solar array atop the Holliston parking structure, installed and operated by EI Solutions, will crank out some 320,000 kilowatt-hours (kWh) per year, earning a $0.632/kWh rebate from Pasadena Water & Power—and it provides shaded rooftop parking.
New Energy for Mechanical Engineering
Author Tom Friedman leveled his gaze at a lunchtime assemblage of Caltech faculty, students, and friends and threw down the gauntlet: “Only Caltechs are going to get us out of this problem,” he said. He was talking about three problems, really, that he views as one giant Gordian knot: climate change, the global economic crisis, and America’s dented world leadership. During his most recent campus visit, the writer of the best sellers Hot, Flat, and Crowded and The World Is Flat, not to mention innumerable “most e-mailed” articles in the New York Times, joined Argyros Professor and professor of chemistry Nate Lewis (BS, MS ’77)—a principal investigator in the Caltech Center for Sustainable Energy Research (CCSER)—in a conversation about these problems. Friedman commented that America’s research universities could help lead the way out of all three with one bold stroke. He’s calling the solution ET—not the alien darling of the ’80s, but energy technology, the challenge of the Aughts. “The motto for America,” he quipped, “should be ‘Invent, Baby, Invent.’”
Invent we will. Caltech already boasts programs like CCSER, which focuses on solar energy, and the Linde Center for Global Environmental Science. These have now been joined by an Energy Engineering Initiative, which was funded as part of a $10 million gift from the Gates Frontiers Fund this September that established the Charles C. Gates Center for Mechanical Engineering.
“One is tempted to say that energy is the technological challenge facing engineering,” says Kaushik Bhattacharya, professor of mechanics and materials science and executive officer for mechanical engineering. “The scale and magnitude of the numbers involved make the problem very hard to grapple with—the amount of energy used, the time horizons on which investments are made. Decisions we’re making today will tie our hands in the future. The challenges we’re facing are such that we have to invest in completely new technologies, but at the same time, we have to address the intermediate time scale.”
Solving these problems requires expertise in many disciplines, but that only whets the appetite of Caltech’s ME faculty, which has a staggering intellectual diversity. Fourteen of the 19 professors have joint appointments in other fields, from geophysics to materials science.
The initiative will attract new faculty, students, and postdoctoral scholars with their own ideas and research emphases. It will also expand existing ME interests in areas such as fuel cells and nuclear energy.
Professor of Mechanical Engineering and Applied Physics Dave Goodwin’s group models and develops materials for advanced fuel cells, which can be used for stationary power generation and for automotive power. Goodwin’s models—created with a widely used software package called Cantera that he developed to model chemically reacting flows—predict that solid-oxide fuel cells (SOFCs) could be vastly improved by engineering their structures at micrometer and nanometer scales. In SOFCs, oxygen ions flow through a ceramic electrolyte to oxidize hydrogen in the fuel. The cells make electricity from a variety of fuels already well established in the market, including methanol, ethanol, methane, propane, coal-derived syngas, or even diesel reformate. To maximize the amount of electricity produced from these fuels at the power-plant scale, Goodwin’s group is engineering the architecture of the electrodes using nanowires and nanoparticles to build a three-dimensional, ion-conducting lattice framework that provides easy ion flow and allows rapid gas transport through the electrode. Through their efforts, in combination with those of researchers in CCSER and other Caltech programs, ME researchers hope that fuel cells will become an ideal source of electricity: superefficient, fuel-flexible, and, eventually, powered by clean, renewable fuels such as hydrogen electrolyzed from water by sunlight (see E&S No. 2, 2008).
Several faculty members are addressing what Bhattacharya calls the “show-stopping problems” associated with nuclear energy. With Michael Ortiz, the Hayman Professor of Aeronautics and Mechanical Engineering, Bhattacharya is working to make reactor vessels last longer in the face of bombardment by high-energy neutrons. This would remove a bottleneck in building reactors that reprocess spent uranium to generate their own fuel. Meanwhile, Hayman Professor of Mechanical Engineering Chris Brennen’s work improves several energy technologies, including nuclear reactors. He wrote the book (the two key books, actually) on cavitating flows, whose tiny bubbles collapse with trip-hammer force to chew through valve, propeller, engine, turbine, and pump blades. And Joe Shepherd (PhD ’81), the Johnson Professor of Aeronautics and professor of mechanical engineering, studies what happens when things go seriously wrong—from deflagrations, ordinary fires that spread at subsonic speed through heat transfer, to detonations, their supersonic kin that spread through shock waves.
The initiative will also support research not yet under way. For instance, engineers will be able to collaborate with geophysicists and atmospheric scientists on carbon sequestration—keeping carbon out of the atmosphere by storing it underground—and with information science and technology experts on designing smart power grids, which use digital technology such as sensors and two-way communication to improve the transmission and distribution of electricity from myriad decentralized sources, bypassing traffic jams and cable breaks. Graduate students and undergraduates interested in wind power, solar-thermal energy, and other technologies will be able to design research projects based in ME that draw on talent and resources across several academic divisions.
The Gates Frontiers Fund gift will help support a planned renovation of the postwar Franklin Thomas Laboratory into a state-of-the-art research and teaching facility. Taking a leaf from the successful renovation of GALCIT’s home (see E&S No. 1, 2008), Caltech plans to rehabilitate the landmark building rather than build a new lab. Still, another $10 million will be needed to recruit key people and complete the renovation.
The late Charles C. Gates, a Caltech trustee for 25 years, felt that Caltech excelled at solving complex problems and getting the solutions to market, and he relished the faculty’s disregard for disciplinary boundaries. His daughter, Diane G. Wallach, remembers that he kept up with every aspect of science at Caltech, reading each issue of this magazine cover to cover. A conservationist who loved the outdoors, Gates would have appreciated the environmental aims of the Energy Engineering Initiative. Even more, though, he would have liked its multifaceted approach. “My father felt that Caltech did things differently than other prominent universities. He liked the concentration of energy going into science and technology, and loved Caltech’s focus on the hard sciences. He was an engineer himself, and believed that mechanical engineering should cut across all the disciplines, that we have to get people from all these areas into the same room, get them talking to each other to solve problems. This gift will help make that happen.” —AW
